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تسجيل مستخدم جديدB -> pi, B(s) -> K form factors and Vub determination
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Blazenka Melic
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We present a QCD light-cone sum rule (LCSR) estimation of the B -> pi, B -> K, and Bs -> K form factors calculating gluon radiative corrections at next-to-leading order. The MS-bar b-quark mass is used, instead of the one-loop pole mass employed in the previous analyses. For B -> K and Bs -> K form factors the SU(3)-symmetry breaking corrections are included, both in the hard-scattering kernels and in the distribution amplitudes (DAs). By combining the predicted value for f^+_{Bpi}(0) with the product |Vub f^+_{Bpi}| extracted from the B -> pi l nu measurement, we obtain the LCSR prediction for Vub CKM matrix element.
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